Englishman James Davison sat in for Bourdais at the 500, and ex-F-1 driver Esteban Gutierrez drove the No. 18 car at the Detroit doubleheader. Coyne tried to get Gutierrez, an IndyCar rookie, approved to drive at Texas, but IndyCar denied Coyne's request to let the young Mexican driver complete his oval rookie orientation during a testing blackout period.

That led Coyne to Vautier, who has recently been competing for SunEnergy1 Racing in the IMSA Weathertech SportsCar Championship series. He has two podium finishes in five races.

Vautier, the 2012 Indy Lights champion, has 30 IndyCar races on his resume. He drove 19 races for Schmidt Peterson Racing in 2013, recording one top-10 finish. Two years later, he drove 11 races for Coyne as a replacement for Carlos Huertas and scored two top-10 finishes.